[llvm] [llvm-mca] Abort on parse error without -skip-unsupported-instructions (PR #90474)

[Michael Maitland via llvm-commits]

michaelmaitland wrote:

> Maybe we should add another flag for this particular use case?

> Another possibility would be to have -skip-unsupported-instructions

Either sounds sounds like a good solution. I think there are two distinct cases here:
  1. Cant parse to MCInstr
  2. Cant parse from MCInstr to MCAInstr

We should be careful to not conflate them.

>  That one has instructions in the test case which are not supported (edit: for some variations of -mcpu tested)

I'm more worried about passing something totally incorrect, like passing not enough registers, or incorrect types of registers, or even mnemonics that don't exist. I also wonder if it would be hygienic to have a test case where you run it on multiple mcpu but one CPU cannot accept that program.

https://github.com/llvm/llvm-project/pull/90474